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A part of the thrill of using custom hardware is that eventually you will run across an obstacle. The resistive touchscreen that's used in the Lilliput and Xenarc monitors presented quite the thrill when connecting it to the ODROID-X2.

Upon plugging in the USB connector the initial response is delightful. The touchscreen will automatically begin responding to touch. The problem lies in where those touches occur based on the position of your finger on the screen. The X and Y axes are reversed, leaving you with a touchscreen that cant really be used. Unfortunately, the solution isn't as easy as it would be in Windows, where a simple recalibration of the touchscreen would correct the issue. The driver that allows the touchscreen to operate on the ODROID-X2 is a part of the system kernel files, and the only real way to apply any fix is to recompile the OS with the modified kernel files.

Luckily I have Googled enough to stumble on an easy to use guide to correct the issue and get the ODROID-X2 working in harmony with our standard touchscreen fare. This solution may work on other Android development boards, but obviously your source files will vary.

I must note that I take NO credit for the solutions presented here. It's mostly a combination of information found at these two sources:

5.Configure Toolchain for your ODROID-X2 storage type.
If using the eMMC module enter:

Code:

make ARCH=arm odroidx2_android_emmc_defconfig

If using an SD card enter:

Code:

make ARCH=odroidx2_android_sdmmc_defconfig

6.At this point you can minimize terminal, and navigate to the directory where your kernel sources were unzipped (should be in Home folder, a folder called kernel_4412). In this folder, navigate to the file kernel/drivers/hid/hid-input.c. Open this file with a text editor, as we will be modifying a small portion of the file with the corrected code.

7.Find the hidinput_hid_event() function, and append the following code between the lines that read "input_event(input, EV_MSC, MSC_SCAN, usage->hid);" and "input_event(input, usage->type, usage->code, value);" . You can use the find/search capability to help locate these lines within the hidinput_hid_event() function:

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Sean shows us how to install a backup camera with a Lilliput monitor pre-wired for backup camera connectivity. These special Lilliput monitors have a wire (usually green in color) that extrudes from the back of the circuit board. When this wire receives +12V, the monitor automatically switches from your PC input to AV2, where your camera is connected. So, if you connect this wire to your backup lights and your camera to AV2, when you shift into reverse, the display will switch to your camera input.

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Sean boots up his car computer for the first time. Be sure to make sure all positive wiring is connected to the appropriate accessory or capped with electrical tape before you reconnect the positive power cable to your battery. With any luck, your computer should boot properly the first time. Sean's enthusiasm on the video is testament to the difficulty associated with any car computer installation and his relief is apparent when everything works properly.

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Sean goes over all of the wires that go into the dash from the computer, amplifier, and other peripherals. The BoomzBox is also installed into the dash behind the monitor. This is secured to the frame of the dash with adhesive tape and large zip ties. Backup camera wiring is extended to the backup light. When this wire gets +12V, the Lilliput monitor will automatically switch from PC to AV2, displaying the backup camera through this input. A vehicle specific wiring harness eliminates the need to splice into your factory wiring.